They did it for the money.
The four Marines charged with murdering their Brooklyn-raised sergeant and his bride confessed they were looking for an easy score when they burst into the couple's California home with guns drawn, court papers revealed Thursday.
Three of them ratted out Pvt. Emrys John as the triggerman who ended the torture of Sgt. Jan Pawel Pietrzak and his wife, Quiana, by shooting them in the back of their heads.
All of the suspects say that Quiana Jenkins-Pietrzak was sexually assaulted, but each says it was the other three who did it, the papers say.
Shackled and dressed in prison orange, the Marines avoided looking at each other during their court appearance Thursday. They did not enter pleas.
"John is the shooter," Riverside County prosecutor Daniel Delimon said. He said all four are "eligible for the most severe punishment."
EARLIER: BROOKLYN MARINE & WIFE TORTURED AND SLAIN
John's site on MySpace offered a window into the sick mind of the 18-year-old private from Baltimore.
"Chillin waitin 4 da killin," was the caption under a photo he posted before the newlyweds were executed on Oct. 15.
Elsewhere on the site, John - an admitted collector of knives and swords - wrote that "shooting s---" and "blowin s--- up" was a great "stress reliever."
Lance Cpl. Tyrone Miller, 20, of North Carolina, told cops he threatened Pietrzak with a shotgun to get into the house. He said he bound and gagged the couple and then debated with John whether to kill them.
On his MySpace page, Miller referred to himself as a "Cripgeneral." Investigators are now checking whether he had ties to the violent Crips street gang.
Pvt. Kesuan Sykes, 21, of California, is nicknamed "Psycho" and admitted that he "cut" off Quiana Jenkins-Pietrzak's clothes, the court papers state.
The fourth Marine was identified as Pvt. Kevin Cox, 20, of Tennessee.
John and Miller worked for Pietrzak, who was a helicopter airframe mechanic at Miramar Marine Corps Air Station in San Diego. Sykes lives near the base. The other Marines lived at Camp Pendleton.
Detectives found stolen items like Pietrzak's digital camera and his wife's engagement ring in the barracks, sources said.
Pietrzak, 24, was born in Poland, raised in Bensonhurst, and joined the Marines in 2003. Quiana Jenkins-Pietrzak, 26, was black and from the San Diego area. They met at a party before Pietrzak was deployed to Iraq in July 2005.
"When he came back, she was there," his mother, Henryka Pietrzak-Varga said. "I accepted her like my daughter and her family accepted him like their son."
The grieving mother insisted again that robbery could not possibly be the motive. "I can't believe it's about money," she said.